missing LoraConfig import

docs/source/developer_guides/lora.md

@@ -174,7 +174,7 @@ LoRA training can optionally include special purpose optimizers. Currently the o
 LoRA training can be optimized using [LoRA+](https://arxiv.org/abs/2402.12354), which uses different learning rates for the adapter matrices A and B, shown to increase finetuning speed by up to 2x and performance by 1-2%.
 
 ```py
-from peft import get_peft_model
+from peft import LoraConfig, get_peft_model
 from peft.optimizers import create_loraplus_optimizer
 from transformers import Trainer
 import bitsandbytes as bnb